List of top Physics Questions on Electromagnetism

The dimension of mutual inductance is (Denote dimension of current as A)
A particle of charge $q$ and mass $m$ is projected from origin with an initial velocity $\vec{v} = \left( \frac{v_o}{\sqrt{2}} \hat{x} + \frac{v_o}{\sqrt{2}} \hat{y} \right)$. There exists a uniform magnetic field $\vec{B} = B_o \hat{z}$ and a space varying electric field $\vec{E} = E_o e^{-\lambda x} \hat{x}$ within the region $0 \le x \le L$. After travelling a distance such that $x$-coordinate has changed from $x=0$ to $x=L$, the change in the kinetic energy is \dots
An electromagnetic wave travelling in \(x\)-direction is described by the field equation} \[ E_y = 300 \sin \omega\left(t - \frac{x}{c}\right). \] If the electron is restricted to move in \(y\)-direction only with speed \(1.5 \times 10^6\) m/s, then the ratio of maximum electric and magnetic forces acting on the electron is:

For the given capacitor circuit, find out the equivalent capacitance between A and B: 


 

Match the given quantities according to their dimensions: 


 

A toy gun fires bullets in every possible direction. It is found that the bullet lands at a maximum horizontal distance of 6.4 m from the gun. Find the speed of projection (\( g = 10 \, \mathrm{m/s^2} \)).

Point P is at \( r = 5 \, \mathrm{cm} \) distance from the centers of two bar magnets, each of magnetic moment \( 3\sqrt{5} \, \mathrm{A \! \cdot \! m^2} \). Find the magnetic field at P (assuming magnets are placed such that P is on their axial/equatorial lines).



 

A solenoid of radius 2 cm and with 125 turns is kept in a uniform magnetic field of 0.4 T carries a current of 1A. The axis of the solenoid makes an angle of \( 30^\circ \) with the field. The torque acting on the solenoid will be:
Material of \( \mu_r = 400 \) is present inside a solenoid where the magnetic field is found to be \( 1 \, \mathrm{T} \). If the magnetic intensity here is \( \alpha \times 10^5 \) SI units, find \( \alpha \) (\( \mu_0 = 4\pi \times 10^{-7} \, \mathrm{H/m} \)).
Assertion (A): Free charge cannot exist inside a conductor.
Reason (R): If a free charge is kept between the plates of a capacitor, then it will experience force and it will drift.
A galvanometer is used for making an ammeter of range 500 mA when a shunt of 2 \(\Omega\) is used. The same galvanometer is used for making a voltmeter of range 10V when a resistance of 470 \(\Omega\) is used in series. Then find the resistance of the galvanometer.
For `C' molar solution of weak electrolyte \( A_xB_y \), dissociation constant is \( K \), then degree of dissociation of \( A_xB_y \) at equilibrium is
A weight \( W \) is connected to one end of a wire and the other end is fixed, length of wire is 1m. Area of cross-section is \( 10^{-5} \, \text{m}^2 \). Graph between change in length and weight is shown. Then calculate Young's modulus.
Figure shows an adiabatic container which is divided into two equal parts by an adiabatic freely moving piston. Both sides contain same gas having \( \gamma = 1.5 \). If heat is supplied to left part such that its pressure becomes \( \frac{27P_0}{8} \), find volume of right part.
Consider two spheres A (solid sphere) and B (hollow sphere) each of radius \(R\), kept on a perfectly rough surface. Mass of sphere A is 5 m and that of B is 2 m. If the same force \(F\) is applied at the top tangentially, then find the ratio of acceleration of A to acceleration of B.
In the given circuit, current passing through \( R \) is 1 ampere. Now polarity of one cell is reversed, then current through \( R \) becomes \( \frac{\alpha}{5} \) Amp, then find \( \alpha \).
A charge particle when accelerated from rest by a potential difference \(V_1\) has a de-Broglie wavelength \(\lambda_1\), and when accelerated by a potential difference \(V_2\) has a de-Broglie wavelength \(\lambda_2\). If \(\lambda_2 = \frac{3\lambda_1}{2}\), find the ratio \(\frac{V_1}{V_2}\).
Match the following quantities with their dimensions.
Find electric field, for given electrostatic potential at P(2,3), \( V = 5(x^2 - y^2) \)

Velocity versus time graph is given. Find the magnitude of acceleration of the particle at t = 5 s.

Escape velocity on Earth is ve = √(2gR). A planet of half the radius of Earth has the same density as Earth. The escape speed on that planet is ve / N. Find the value of N.
8 Hg drops coalesce to form a single new drop. The ratio of final surface energy of the single drop to the total surface energy of the 8 drops is

LED (light emitting diode) and logic gates circuit is given in figure. For what combination of \(A,B,C\) will both LEDs glow? 

In the below diagram inductance \(L_1 = L_2 = L_3 = L\). Find the ratio of total energy stored in all inductors to energy stored in inductor \(L_2\). 

A charged particle is moving in a magnetic field \[ \vec B = (3\hat i + 2\hat j)\ \text{T} \] with acceleration \[ \vec a = 4\hat i - \frac{x}{2}\hat j\ \text{m/s}^2 \] Find \(x\).